Apparatus for testing and classifying insulating sheets according to dielectric strength



Aug. '12, 1947.

F 'R. SCHMITT 2,425,347

APPARATUS FOR TESTING AND CLASSIFYING INSULATING SHEETS ACCORDING TO DIELECTRIC STRENGTH Eiled Oct. 7, 1942 e Sheets-Sheet 1 flqi P1215.

ATTORNEYS APPARATUS FOR TESTING AND CLASSIFYING INSULATING F. R. sci-mrr'r SHEETS ACCORDING TO DIELECTRIC STRENGTH Filed Oct. 7, 1942 6 Sheets-Sheet 5 Aug. 12,

g- 12, 1947- F. R. SCHMITT APPARATUS FOR TESTING AND CLASSIFYING INSULATING SHEETS ACCORDING TO DIELECTRIC STRENGTH Filed Oct. 7, 1942 6 Sheets-Sheet 4 INVENTOR flan/21?, Jab/radii BY ATTORNEYS Aug. 12, 1947. F. R. SCHMITT 2,425,347

APPARATUS FOR TESTING AND CLASSIFYING INSULATING SHEETS ACCORDING TO DIELECTRIC STRENGTH Filed Oct. 7, 1942 6 Sheets-Sheet. 5

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' APPARATUS FOR TESTING AND CLASSIFYING INSULATING SHEETS'ACCORDING To DIELECTRIC STRENGTH Filed Oct. '7, 1942 6 Sheets-Sheet 6 II II/ v INVENTOR 15 ITmn/ZKfibkmiif BY dwJmqw ATTORNEYS O CE E 'AP'PARATUSFoR rEsTiNG'AND oLAssIFY:

IING INSULATINGSH-EETS ACO DIELECTRIC STRENQTH' ork, N

" seats. sta e-refs w.

v "New Bedfiord; Mass; 'acorporatio 1 ,Application bctob ers'lrlflz, se i ,7 V,

the mica sheets used condensers.

Since the culling: of mica sheets for condenser:

dielectric use by visual inspectionis. a costly oper-:

ation which is not uniformly reliablein that-it'd:

, jmesne assignments,..to. Aerovox'jC poratio M frequently fails to disclose latentdefects gthat become evident only after assembly, and some-e times after installation of the condenser, -.it is a fundamental object of the-invention to'pro vide. an automatic machine for testingsheets. of mice;

or the like, automatically andv speedily ,to classify:

them according to ,their diclectric, efiicacy and J with absolute dependabilityto'segregate'the good. sheets or those that meet specificationszfrom the-"1- N I, H y H v v v taken on'line [O l0 .ofFlg. 5 a

bad ones, 'or those that are ,below specifications,

so that no latent defects will develop in condens- .takenon linev LI -l I, of F g.2,and

ers built from-the selected mica or other di-;

electric sh'eets, and tremendous economy-'in'the cost of condnsers'istheteby initial'and service effected.

' It is among other objects to provide ,a' machine of the above type which will'assure the testing of only one sheet at a timeg'sdthat the test'ingf response will not be impairedwere an extra. sheeth to remain in place during the testingoperation,

which will be proof against operation when ,thef" supply of sheets to be tested has been exhausted Or when any the magazines mWhiChTthe-SF "izine 2'0}cqntainingthesheets, tobe testedand lected sheets are stackeclis full; an,d which will be proof against operation while a magazine is i being replaced, all to as'surethat the machine will test reliably at all times and that 'it issubf oo'f both against, idle operation. and,

stantially pr against injury to the operator.

The sheet feeding means'and thel maig azine f herein disclosed are the subject-mattergof a di-f visional applica In the v accompanying drawingsj'in I ible embodiments or) shown one of various] pos the several features of 'th'e'in'vention i Fig. 1 is a view in side elevation ofthe com pletely assembled machine Fig. 2 is a side elevation ona larger scale vc the hedof'thejmaf the operating portions abo chine as shown in Fig. 1, 1

Fig.3 is'aview in"front elevation spartly in:

section, looking in the direction oi the arrows,

on line 3-.3 of Fig. 2,

Flaws a view similar to p w moved showing "the machine in the process of ref;

jecting a defective sheet,

*supplyfi eg i block and associatedlstructure,

. chine a bracket. I9 under the" bed] 5.

. The testing b lock,.best,shown- ORDING TO' Fig. 5, isa view. in transverse cross on lir ief5] TofFigS, I avi w onla .,somewh at..largerfscale, pneumatic valve, operating pain and ed str jc refa tak on n'e e s 6i mentfo'fthefpneum'aticcontrol'va1veplate,

Fig; 1751s a'view; on alarger scalefiri'longit idinal cross-seams howing' th' construction or the c 'l I-T 1' 1" 'a'similar .view showing the t ting Fig. ii ,is

isl -d a J wata e Fig' ill- 3 Fig;,1 0, ,is a view in transverse. eross section Fig. 11 is "'a' view in transverse"cross-sectio e. 2 i a r ui d a ram,i hqw ihlt r e ted fin I the a ous electrieall controls incorpo a Refer i shown in Fig. 1' has a sewer bed plate |5 "carried"- 25' imodated a vacuum ta'nl; lly lgept e haustedby; -a suitable vacuum pump (not shown). The operon support legs l6 between which may beaccom-lj ating motor" I 8 'forthe machine is suspended from 'I Upstandingon the bed I5,arethesupplymaga ii I classified, thetestingblock 2 l ,;the collector maga; 1; I l r 7 I v a corresponding sock. 25 mounted upon thebed, l

i i inein 'ih' s magazine.

J o conv nie cethe. s pp enieq le t r m zines may be interchangeable. i However,'.,'since,

.in manner to be described presently.'

V v in ie. ICOIn-z. prises a conducting'rodiq,whichl passes through an insulating bushing 3! affixed by screws 32-into pushed downward as'sh'eets are pressed .thereint o i hereinafter,

.machi'n'e'; A y

The sheets fromthe supply magazine 20 are successively-tdbe 'pi'cked'oif therefrom, by resort .valve base I28.

1m block 2|, where it deposits the sheet. selector head 44 has a backward and forward the bed Band is encased by an insulating cylinjder 33 aflixed in a socket 34 upon said bedand having insulated bushings 35 therein, which maintain the rod in concentric relation relative thereto. Slidably fitted in the upper end of the testing block, is 'a metal platform-36 affixed by screws 3! upon leaf sprin'g'38- of U-shap'e, with sinusoidal legs, theends of which are afiixed by i a collector magazine, the range of movement of through'the testing head 44 hereinafter to be described, which presses the sheet to be tested 4 against platform 36.

' Referring more especially to the enlarged detailed views of Figs. 2, 3 and 5, the motor -l 8j enves'a'sheave' wheel 45'by a -belt'46 extending through the bed and driven from a pulley 41 on the motor-"shaft. 'The 'sheavewheel ismounted' 1 upon a jackshaft 4 8 carried at one endina main upstanding bearing plate '49 supported uponthe bed IS -ancIFh aving a second journal in a bearing bracket iio also bolted' to said bed. The jack shaft carris'a 'small gear or pinion l'which'm-eshes' 7 the selector-head being determined byihe char- 1 acter of-ithe sheet being tested'fto classify the' sheets; asgwill be more fullyset' forth hereinafter. h It will, of course, be understood that th suction heads must lift free of the .magazine and 10 testing ,blo'ck respectively before they can move laterally-from. the supply magazine to the test- --ing-i. block, and from the testing block toa col- 7 lector magazine respectively, and cannot descend intosuch delivery station i'mtil concl sion of the lateral tramsferfllfor transport movement. .To

bring this-action. about it has been found ad- 'vantageous to move the two suction heads vertically up and down in their lifting and delivery 1 action, and to transport them horizontally in the intervening travel between ..the stations of pick up and delivery,

with a larger gear 52 upon acam shaft'53jdesir- I ablysomewhat behin'dandabove the jack shaft. iThe cam shaft 53 has a bearing at one 'end in bearin -"plate 4-9 and a second bearing in bracket 54. Uponthe cam shaft are rigidly affixedthe to apiek up head "fidnorma'llyregistering with the supply ma azine 2Das shown in Fig. 3 and to various cams,="three in number, to be described 7 j which determine theaction of the A 'I'he-pick-up head in th'e'preferred' suctiomop- 1 eratedem'bodiment is perforated'at its lower face as at 51; its upper face being threaded upon nipdeposited upon the testing-block;

Thetesting'or selector head 44, preferably also suction-operated and of the same construction :as the pick-up head 56 is normallyinregistry with the testing block (Fig. 8) and its normal function i's'to close the testing circuit and then Reverting" now to the drawings, the 'bearing' 7 "plate is-provided with two'sets ofbearings "61 V v and GZ- at'opposite ends, thereof that accommoQ f date a rail structure, desirably a pair ofhorizontal parallel rails, preferably slide tubes 63 and 64. Upon the rails 63, 64 is a carriage 65 which 1 comprises a bracket 66 having a pair of parallel,

. horizontal sleeves 61unitary'therewithand em-:-

bracing the tubes 63, 64 and affixed theretojas 'f for-instance by taper cross pins 68. The sleeves 61 of the carriage 65 have eyes Hi-and -H that: slidabiy accommodate the tube 59 upon the lower; end of which is carried the pickup suction head. 56, and to the upper; end of which theflexible suction hose. is connected-as previously de I scribed. The tube 59 is afiixed by meansof cross' pin 12 to afcross bar .13" provided-with rollers 14 that ride in a track comprising-a pair of, rectangular bars 16 affixed as by screwsl'l to a backplate'il. w

Theselector head mounted an riage 80, generally similar in construction to the; be transportedfor laying the sheet upon the testcarriage and. similarly mQunted the Slide ingblockil. i- Y rails 63 and 64, exceptthatsaidcarriage is not rigidly iaflixed to the slide-rails as is the (carriage In handling a dielectric heet which. isup tostandard, the carriage BD isentrained, as aunit with the slide rails 63, '64 by tension througha .;draglink'3i pivotally aflixed 'thereto'atone end, q 1' as at 82, and'flxed at its other upon'a pivot 33, V

.threaded'at 84 upon disk 85' keyed at;86 ,upon axle 81 through a tractorframef88 that has sleeves. which encircle the respective slide rests.

:63, 64,-"and'whichare rigidly aflixed' to said rails,

to pick up the tested sheet and if up to specificaj tions to'deliver it'to the top of the collectormagazine22. v e

As' will be'described hereinafter, arrangement is made 'forselectively advancing the selector head-44'through a longer pathin response to the test of asheet below specifications, to deliver the :same unto the rejectmagazine 23. f

Thus, the pick-up head 56 is constrained to" have acdnstant backward and forward move merit from'the top of the -supply'magazine20, 7 V heads 56 and 44 is effected in unison by lifting.

the elevator track member l5"and with it the] cross bars 13 and El a'nd'the tubes 59 and ilfl rea by means of taper crosspins .(n'ot shown) Uponany sliding movement ofthe' rails j63,164;. the pick-up carriage 65 (which mounts the pick-.,

up head' 56)' will move as a unit Withsaid rails and the fixed frame 88 whichalso moves with the railsjwill entrain'th'e 'selecto'rcarriage 80"by tension transmitted through the drag link ,BI,

so as likewise to move as a unitwith the rails.

As inthe case of the pick-up carriage 65 the H selector head tube 90 vertically 'slidablein the elevator track'15.

The up' and down movement of ,thesuction1 4 movement from thetop of the testing. block. where it transmits testing current, then picks upthe tested sheet and transports it to the top of spectively afilxed thereto," that carry the respec= tive pick-up and selector'heads 56 and. The mechanism for lifting the "said elevator track membercomprises" the elevator cam' 92 aiiixed to the camshaft 53, presenting a closed generally" circular groove" 93 vwith diametrically opposed; outward enlargements 94*and 95. Roller 96'onthe end of anarmffl rides within groove'93, The oppositeend of arm 9'I'is keyed upon'an' axle 98 upon which is also keyed an upstanding arm 99 pivoted at it'supperlend toafshort link :|32 -which encirclesai'd bolts, against a" movable valve plate 133interposed betweenth'e cover plate' andfthe 'valve' base. 'The movable 'valveplatef is pivoted upon'fcross shaft '-I34 through 'the standard l2'l' -and'is generally Y- shaped. ""Ithas an upstandingearm -I35,'the up per end "ofwhic'h serves as the valve proper, 9.

'"- generally qe'wnwaraly directed arm "I36; which carries the'rollerl31 that rides'upon the cam I I00. the opposite "end of which is pivotedto'a collar IIlI rigidly ailixedupona horizontal rod I02 threaded into ferrules l03'atthe opposite ends thereof, that are secured upon the rod by nuts I04; The ferrules at opposite ends of rod I02 have respectivelypivoted thereto upstanding links I05 and I06. keyed upon corresponding stub shaftsIll'l and I08 bearing in the plate 49," to

which are also keyed generally horizontararms I69 and III] respectively, which extend toward the right in Fig.3 and are pivoted at their free ends to near the opposite en I8 of elevator track member'IS.

The lateral movement ofJthe carriages 65 and ds of the back Plate 80 with the slide rails 63, 64 that carrythemji'sb effected from' transfer or transport cam III which is also affixed upon the cam shaft 53L Cam III has a closed cam, groove presenting a 1 circularlarc N3 of smaller diameter, a circular and a third"outstanding arm I38 urged down wardby Qcoilspring I39 fixed'to the end thereof; and anchored to'th'e becl at its opposite end' l4ll.

The upper bolt I3I is above thelupper end of movable'valve plate I33, while the lower bolt I3I 1 passes through elongated aperture I through 'said'fplat'e, to permit movement for the latter. When port I 42' throughyalve p'late I33 registers with the port I29 through valve base'l'28 -and correspondingport I43 through valve cover plate I30, suction is effectively transmitted from the vacuum tank I! through the conduit I26 and thence from the valve to conduit to'the two suction heads 56 and 44. The valve'plate I33 is movable to bring aperture' l42 out of registry with the aligned ports" I29 and M3 and to bring into registry with" port I29" n t L|45l in 1 .1: valve'-plate,*which is effective to 'vent th'esuction V heads and thereby discontinue the suction;-

arc II4 of larger diameter and connecting arcs II5 therebetween. Cam roller II6 upon the .up-.

per end of arm I I1 rides in cam groove I I3-I I5; I

The lower end of arm II'l is keyed upon axle II8, which latter has rigidly affixed thereto a longer arm I I9, the upper end ofwhich is pivoted to ashort link I20, the free end of, which is pivotally connected at I2I to the pick-up carriage that is fixed to slide rails 63, 64.

The stroke of the slide rails in the transfer ortransport is equal to the distance between the supply magazine 20 and the testing block 2| I which in turn is equal to that between the test- 7 ing block 2| and the main collection magazine 22.

It, therefore, follows that in the transport action, the pick-up head 56 willtravel into registry with the testing block 2 I and the selector ,head 4 4 will come into registry with'thecollector magazine 22.

The elevator-cam 92 and thetransport cam III are so timed that the transport action only commences after the elevator actionthrough camenlargement 94 has caused, the suction heads to 7 clear the magazines and'the testing block, and I 1 the suction heads descend into magazine orteste ing block through the action. of cam enlargement 95 only after the conclusion of the transport action.

In properly timed relationship withthe elefro-appl the high tension'testing'burrent at the correct instant to :the'te s tir'i'g blockupon which a sheet had been laid by thepicklup head 5'6, amer-15o mounted-on the camshaft 53 'is v introducedin thetest 'circ'uitfa's indicated in' Fig.

12, so that the high tension' currentis-applied for an instant-when the testing or selector head 44 presses the dielectri'c sheet to be tested snugly intocontact- 'with the platform 36' therefor.

lation for the desired purpose.

When a sheetis being'test'ed that has good" e electr-ic' 'propertiesf lie. one that will not break through or permit excessive lea'kag'efthe leakage current through" solenoid coil I 5I willbe 'insufli -cient to actuate the same, so" that the selector head 44 will subsequentlytransfer the testedsheet to collector magazine n in the. manner 3 gpreviously'de scribed.

vator and transport cam action is the applicationv of the suction to the two heads for the pick-up action, and the discontinuance of such suction for the release action; That'action is controlled by a third or pneumatic control cam I25 upon the same cam shaft'as the other-two cams 92 and III. For the application and discontinuance of the suction, the suction tube I26 from the vacu- 60 3 I. through the apertures I53 in the platform 36 of the testing" block to blowout any sheet that may l um tank is connected to the respective suction 9 ,heads 56 and 44 through a valve structure shown 5 v applied througnthethickness0i a single sheet in Figs. 5 and 6. r v

The valve structure comprises a, standard I21 mounted upon the bed I5 and conformed at its upper end as a fixed valvebase I28 with a port I29 therethrough leading to hose 60. A valve 4 cover plate I30 mounted on bolts I3I through the fixed valve plate I28 is resiliently pressed by Immediatelyafter the selector head 44 has left the testing"block"2l,' a blast of ,air is blown not have'bee'n picked upby the selector head in the previouscyclel duefor instance to jamming ink-place thereon. There is thus assurance that if tlie's'elector-head shall have failed to pick up a tested sheet, the same will be reliably expelled,

so that thetesting'current will inea'ch case be only rather than through one or more superposed sheets. The-timing of the blast blown through nozzle I'I'9' inthe side of the testing block mayjf be controlledfi'om any of'the cams in manner' readily understood and, therefore not shown; If the dielectric sheet should breakidown'or thus be urged back bytpnng' I99 to gripthe edg'es'of the upper sheets in the stack, so that the r catapulting of sheets under the resilience "of the compressed stack will not-occur upon withdrawal of the suction head from the magazine.

Inasmuch as the pick-up headhas a fixed up and down stroke, it isimportantthat the upper dielectric sheet in the supplystack be urged upward so as to assure engagement, thereof with the suction head, even though the supply in the stack nears exhaustion. To that-'endthe follower 26 is provided with a rod 200' extending axially through the socket 25 of the magazine, a crossbar 20I being secured to the lower end thereof by nut 202. A pair of long coil springs 203 anchored to thevends of said crossbar at their lower ends ingcircuit fromthesec'ondary221 i a"lQW v.0lt-

age'tfansformer whoseprimaryis at 229through' Solenoid 229 opens switch 230 Q '1 which interrupts the circuit to relay 23I. [The current tocoil 232 connected tothe third main thereby is spring-urged toopen circuitposition.

are connected to pins 204 protruding from the lower part 25 of the magazine socket 25. It is desirable in this connection to have the. u'pwardf thrust of springs 203 occur only after the suction head has entered the magazinefand while the lateral shoes I92 are released. Tofthis end the rod 200 extends through an aperture I99 in a' brake arm 205 pivoted to .a lug Ii in'the base of the magazine socket and urgedobliq uely, upward by a coil spring 201 anchored at onejend to a crosspin 209 through the free 'end of said arm 205 and at the other end to a pin 209 in the of the collector magazines 'isnlled;

base 25', so that thediagonally opposite edges of the aperture I99 in the arm. will grip therod tion by the springs 203'. o I

Momentarily to release brake arm H 80 200 and brake 0r lock the same against operaf.

265 'at'i the desired instant, there is provided a cam lever 2 I0 1 pivoted about axle 2H and having an oblique lower cam end 2|2 engaging the crosspin 209,-so that when the lever is shifted to. the, right in Fig. 7 through but asmall angle, the arm'\205 will be pushed downward slightly to relaxits grip upon the, 'rod'200,.which will thus be spring- 'urged upward for the desired purpose. The lever 2I0 is preferably operated from one of the cams,

desirably from the elevatorjcamf92. Forthat purpose cam 92 is provided with an enlargement or abutment 2I3, desirably attached to the periphery thereof which may l come into contact with roller 2| 4 upon the upper end of the lever 2 I 0, so that, for the short interval that said short enlargement engages the lever, brake-arm 205" will release rod 200. As soon as the. abutment 2I3 has passed the lever roller 2, the lever 2I0 will ,be summarizedior ease "of reference.

will be pushed back to the position shown in. I

Fig. 7 by the action of the spring 201 and the crosspin 208 against the cammingend 2I2 ofsaid" lever 2| 0.

Desirably, the various magazines, :0, 22 and 23 are removable from the bed of the machine, for replacement. To this'end the socket of each 1 magazine is providedwith a hub 2| 6 *that encircles the rod 200. The socket is laterally introduced through a corresponding slot 2I-1 in the bed I5 of the machine, the jfianges m on the socket base engaging the faces of said bed. Each magazine'is kept in place'by a corresponding latch 2I9 pivoted at one end vto the edge of bed I5 to I one side of the slot 2| 1 and having a notch 220 at the opposite end straddling the shank of the screw 22| at the opposite side of said slot.

The magazine has lateral studs 222 protruding outward from the lowerpartthereof and passed through lateral slots 223 in the socket 25 through which the magazine-is laterally introduced.- It

is secured in place by tightening of the nuts 24' threaded upon said studs,

The machineis also equipped with-means" for through suction hose 60 automatically interrupting the operating circuit when the supply magazine is ernpty or when any of the collector magazines-is full. To'this end,

thefollower 26 in the supply magazine is brought into contact'witha leaf spring 225 (Fig.2) which protrudes into the magazine through aslotj 226 therein, so that (see "Fig. 12) the follower when it reaches the uppermost position closes agroundsolenoid 229.

m ofthe. three phase circuit shown is. therefore,

interrupted, and contactor1233 thus released Relay 23l is of the type that will recluse only by the latter reaches the lower end i. e., when the magazine is full. These connections are, in the samegroundingfcircuit, but in parallel with the connection 225, eration abfove set forth will occur whenever'any To permit manual operation of the machine,

particularly for Tadjustment purposes, the Jack a shaft 48 is providedwitha hand wheel 48'.

Operation V While the operation has been indicated ijn 'thef," course of theabove description, such operation:

v2a being filled with The supply magazine tested,' the relay 23I is stack of the sheets to be manually reset, thereby 'to close circuit from 7 main m throughactuatingcoil 232, which effects' closure of the maincircuit "through contactor m; The electric motor I8 drivessheave," wheel 45 through pulley 41' and belt'46. Sheave 40 L011 which'it is wheel 45 turns jack shaft mounted and throughpinion 5| and gear'52 drives the cam shaft 53. I i

As the operation proceeds, grooveenlargement 94 of the" elevator cam 92 depresses roller 96 and'moves arm S'Ito rock axle 98 and with it to movearm 99 to th left (Figs. 3- and4).

Through link I00, said arm shifts collar IN and with it rod I02 tive axes I01 and I08 and thereby rock the asso ciated links I09 andv I I0'downwardto'moveiflthe" elevator track 15 downward, and the cross-bars '13 and 9| are moved downward suction heads thereby enterrespectively the supply magazine'20 and the testing block 2 I. At this stage, the pneumatic control cam I25 (seen-g; 6

depresses roller I31 and moves the Y-shaped valve plate I33 about its axle I34 to 'bring the port I42 into registry with, the corresponding ports I29 and-|43 respectively in the'fixed plate I'28 and-the cover valve plate I30 (see Fig; 5).

The suction from the vacuum tank I 1 is thus effectively applied by way of suction tube|26 sheet in the supply magazine 20, while selector v A to theleft. By thataction, they links I05 and I06 at theendsLo'fs'aid rodare moved in clockwise direction about their respec therewith, caus ing the suction heads 56 and respectively to j be pressed vertically downward therewith in their v, v bearing'supp'orts in the respective carriages. The

to the two tubes 59 and. 90, s'o that pick-up head 56 will attract the top I99 which moves in unison cwiththe suction head zinelth e lug'2I3 on thegelevator earn 92 i the'roller' 2I4 ;on' the upper end of leverzlll and -ing*2I I; to cause the lower cam end'2l2 thereor slightly 'to V V the resistance of its springilll- The springs 20 3 f are thus released for upwardsm ovement of the I follower 26'jto 'pressjthe jstackrupwardj'for its top v 1 sheet tobe pressed against the'suctionheadfifi in its return,

an instantland toiap ly h v t si u t I testing h ck, the-blast of air. through nozzle n9 v protrusion 94 on its groove-9.3, so that it promptly I the "shoes l92nto re-engage the stack,- so,that.;

As thefsuctio'n" head as rreacheslthetop the stack in the supply;magazinel flfit e pilot rOd reaches .7 and engages the oblique lug ';I 91 onrthe 'l86fto'shift thegri'pping shoeIIQZ out. 3 the resistance of spring I89 vpin and slot connection, I-94-f- 1o I 961 similarly to shift'fthshOh of the c":ompanion lever'l88. t f, lj While the pick-up headlis' inthe sup'ply magareaches c v v 15 thereby pivots the latter outward ab'out'its 'bear-- depress the braking 'arml 205 against so short that the braking' arm 205 is" released for but'aniinstant; the springjZllIf shifting the ar'mi205 back'tdthef g positionjshown'in Fig; '7' and rel'ockin'g. the rod] The" m us is;

While the selectorhead 44 'is 'pressed upon the testing block 2| as "abovenoted,,the'timer I50, will have' 'reached a; position to clos contact for" 30 in the drawings, illustratively"5000 volts, to the sheet on the platform 36, the circuit being made through said head 44. The pressure applied by the selector or testing head 44 will .betaken resilientlyhyfspring 38, and the circuit will be reliably completed without ,the danger of a. loose y contact in the case .of an. exceptionally thin sheet or of bircess e fpressure upon an exceptionally thick heeth 'efore the selector headentersthec out any; sheet; that may .h'ave become jam ii dag "inst platform 3B in-the previou cycle., Assumingthatthesheet being tested is up to specifications; as ordinarily it should be, .theleakage c r en hro h th te ed s w ei suflicient to actuate the relay I-5I, so thatno rotationof dish 85 onirame 88 will occur, r The elevator camllz as noted has but a short urges the roller 96 inward again to. reverse the depressing movement, previously-describedand to elevate the: elevator track 15. In that elevating action, the pick uprhead while under suction will lift the uppermost sheet fromthe 'supply stack; to clear themagazine, and the selector head ke- 1 clear the testinghlock. f

Before the head- 56 clears the supply magazine. 20, the pilot-rod I99will have become disengaged fromfthe lugl'9'l and the spring l89 ,will cause sheets from the latter will not upon clearance; by the" suction head, he catapulted upward by virtueoftheirresiliency. 'Whenthe section heads 56 and 44 have thus cleared'the supply magazine andtesting head, I the transfer or transport operation sets in Cam, groove portion 3 .of cam; III moves armJI-I;

th ough roller H6 in clockwisedirection (Fig. 3) 70 about itsaxle. I I8 and correspondingly moves arm H9, which latter through link I20 pullsithe car-Q riage 65 towardithe right in Fig. 3,- and-since said earriage is clamped to the guide rails 63, 64, the latter are moved therewith to the right in their Y master operation 'Ther-transfer strolie is such; that the I and. through drag link fll entrainsthe sliding s e- 5,

'. currently with t e movement r the pick' up head, 'it releases the staclgholding shoesiin the csame If? therefbe no "sheet onthete sting "mother's v. the ensuing movement ofthe slide rails63, 64 to the right, the gearl'l3 in.frolling ;along rack I14;

will, therefore, rotate the drum I61 ,therewithi;:.;

i Drum I61 "drives axlBTtofwhich it .is keyed, s which, in turn-, rotates the diskyafi keye therveoh. t- The pin; 83 ofthe drag link.8'l is. thus carried 7 around by disk 85 from the trailing position shown in Fig. 3 throughlSO degrees totheleadingfposiebearing 6| a atz, the rollers 1-4,:and,92 o vtheggff cross-gbars 1 3 and- 19i;respectively,,riding along ra hic rem ns fixedv during; 1 61 pick-up headjfi rnoves from Iregistry with-the supply magazine 20 ,toregistry with the 'testing jlever I81"andtherebyzrocksthesamejaboutits' 1": block 2|. ,The frametflf being likewise. elampe'd Dpiv t i 1 of slotfll93 against 1 and throughjthe to the slide railsj' is moved asi aj'unit therewith A lector carriage 8 0,; sotl' at the selector liea d44. withrthe tested sheet carried therebyenters into'v registry with the collector magazine 22;

At that stage, the' enlargement 95" elevator track 15 to ,move downward and tothere-f magazinejzz. a v v I s the selector head movesidownward, co

manner as previously .:described with respect to" the supply magazine and it depresses thestack and the corresponding, follower 21 through the n l 280 against further movementby the'spring 2B3. thickness of the sheet, deposited ;thereon.,l f fl the'suction headslre'a'ch the lower errds of their respective v strokes inthe testing meager and the collector magazine 22 ;"thepneuma'tic con-'5 V,

trol valve cam .125 moves the 'v'alveplate I33 to bring the notch lthereof into registryiwith'ther shift the carriage 65 and withfitthelslide rails 53,1 V

64 and the frame 88 to the left and through'the drag link 8 I: the carriage 80 is-shifted-back'there-- with to the initial position'for repetition of th cycleset'forth. a

a sheet'on the testing lclloizl;'sl 'o'uld test below standard, theleakage current therefrom is ls'uf I ficient'toactuat the re ay sl and closjeswitchj I I54 (seeFi'g. 12). The-circuit thereupon is closed}? fromvmainfm through'switch I54 to solenoid l55f Solenoid I55 (seerFig's fi 9 and'10)'x'no'tfesthe g free'end of lever I u'pwardand lifts the bar IB 3,, 7,

thereby "top'ermit' the spring I'IIf to press .thefl pawll carried on'drum I51 into" the notch 'o ffl 1 I ratchet wheel [69! i and accordingly to lock the g wise under suction will lift the tested sheet to ratchet Wheel and gear I13- tolthe, drumjl 61, In

tion shown in Fig. 4. Accordin l thecarriage which is-slidable-ontheislide rails is advanced l1.

- during the movementzof the slide railsthrough the I 7 added path imposed by the effective throw of' the drag link 8I ,so that the selector head carried '2; thereby is broughtinto' registry with the secondrqg magazine .2 3;where the defectivesheets, areeto. be-E.

deposited- 1 e g I .1 a In the aflirmative drive of thedrum lfi-lthrough the gear II3,-the strap I15 is caused to tension:

. fl h f r-lr L vator cam.92 reaches the roller 9I to-.cause;the.;.,

the spring within thetension reel I "and to take cuit through solenoid I55 is nevertheless maintained closed until it has performed its function. For, relay I51 in parallel with solenoid I55 closes .switch I58 simultaneously with the original actuation of relay I54. The circuit of solenoids I55 and I 51 remains closed because it extends from main m, lead I59, switch I56, relays IIand I 55 in parallel back through lead I56 to companion main m 1 I At the extremity of the stroke of slide rails 63, 64 to the right, that'is, when the transport or transfer has been completed, leaf spring. I80 is raised, therebyto open switch I82 (see Figs. 3 and 12) so that the circuit to relays I55 and I51 becomes interrupted. Spring II'I therefore, de presses the free end of lever I60. The gear I13 is turned back in the return movement of the slide rail 63, 64, and through pawl I it drives drum I61 to return drag link 8| to the trailing positionv shown in Fig. 3. Near the end of this return.

movement, roller I64 of pawl I65 reaches and is pressed against bar. I63 to release the pawl I65 machine and many ing from the scope'of the claimsgitis intended that all matter contained in the above description 'or shown in the. accompanying drawings, 7 shall be interpreted as illustrative and not in a limiting sense.

Having-thus described my invention,=what I claim as new and desire to secure by Letters;

Patent of the United States is:

1. An automatic electrical machine for to the testingblock, means for applyin'gtesting out of engagement with the ratchet'wheel I69.

The stressed wound tension reel I16 now holds the drum I61 and with it the axle 81 and disk:

85 and the drag link 8I in position shown in Fig. 3, preparatory for the nexttycle of movement. above described, of selection or rejection, as-the case may be. In the return stroke of the transfer mechanism, the suction heads will accordingly return to the position shown inFigf 3.

When the supply magazine is completely emptied, the follower 26 will have approached the upper end thereof, so that it engages the spring, 225 to close-the grounded circuit (se-e l2) from thelow voltage secondary 221 through the relay coil 229 to open switch 230. 'The relay 23I then opens to de-energize the contactor operating solenoid 232 and to interrupt the circuit from the mains. Upon removal of the supply magazine in manner clear from the previous description and replenishment thereof by a fresh magazine, circuit cannot be closed until the relay'23I is manually reset, so that the operator is protected.

Exactly the same operation occurs when either of the collector magazines 22 or23 has been completely filled, in which case the grounding circuit is established by engagement of the follower 21 with the associated spring 235 at the bottom of the magazine It will of course be understood, that whilemagazine 23 was designated the reject-magazine, the sheets therein may nevertheless be useful either for condensers. of lower specifications or when used in pairs, may afford sufiicient (ii-electric strength for low capacity high voltage condensers The machine is not necessarily limited in its utility to segregaterelatively unsatisfactory from. satisfactory sheets. It could beused for instance to sort sheets for their respective dielectric capacity. This would predetermine the inherent capacity of each sheet, thereby making it possible currentto each sheet while on the block, means forfeeding the successive sheets -irom the'testing block,and means responsive to the electrical property of anormal sheet as determined 'on the testing. block to deposit such sheets in one' magazine and an auxiliary drive responsive to the/testing current on a defective sheet to superimpose. upon said normal feed a further displacement upon the sheet to deposit the rejected sheets in the other magazine. I f

2. In an .automatic'machine forclassifyi'ng dielectric sheets, the combi nation -of' a supply magazine, 'an electrical testing block, means for applying test current therethrough, and collector magazines for the respective classes of tested sheets and at different distances from the testing block,"a bed mounting said magazines and said block,..a pick-up head, means for moving the same from the supply magazine to the testing block and return for picking up successive sheets from the supply magazine and transporting them to and depositing the same-upon the testing block,

a selector. head, means for moving the same from the testing block to a collector magazine and return for picking up the successive sheets from the testing block, and transporting them to and depositing the same upona collector magazine, and means controlled by an electrical characteristicfof the sheet determined at the test block, se-.: lectively tocontrol the length of travel of the selector head for deposit of the sheet carried thereb in the corresponding collector magazine. I

3. In a machine of the character described, in

combination, a supply magazine, an electrical testing block, abed mounting said magazine-"and said block, a rail structure, carriages mounted upon the said rail structure, one of saidcarriages having a pick-up head normally registering with said supply magazine, means for causingrela tive movement of approach and recession of said head and said supply magazine for picking up a sheet from the latter, means for causing move- 1 ment of said pick-up head lengthwise of said rail structure, for registry withsaid testing bl'oclqdeposit of the sheetthereon andreturna of said head to assemble a stack to a very close capacity-toler-v ance. gauging the dielectric sheets for thickness. 'The As many changes could be made in the above This would be even more suitable than.

to registry with the supply. magazine, a testing head on: one of said carriages for coaction with said testing block and the sheet thereon to be tested, and for transfer thereof for removal ofthe tested sheetfrom the testing block after the testing operation.

4. In a machine of the character described, the

combination of asupply magazine for dielectric sheets, a testing block, means for applying test- 7 ing current thereto, and a plurality of collector magazines for the classified sheets, arail strucwidelydifierent embcdinients. of this invention could be-made without depart- -selec-, tively rejecting below-standard dielectric sheets, I said machine comprising a supply magazine, a ,testing block and a pair of collector magazines,

one nearer the testing -block for the. selected,

ture, a pick-up head mounted thereon anda selector head normally registeringrespectively with the supply magazine and the testing block, means for moving said headsin unison, automatically'- to; shift the pick-uphead to transport a sheet to the testing. block and concurrently to move the selector head to pick up the sheet from the testing block and deliver it to one of the collector magazines, and means controlled by the electrical response of the sheet being tested on the testing block to move said selector head to a correspond ing position out of registry with said collector magazine and means for effecting discharge of the carried sheets respectively to the testing block and to the collector magazine selected by'the test.

,5. In a sheet dielectric classifying machine, the

combination of a bed,,a supply'magazine, a test- I ing head and collector magazines all mounted upon said bed in aligned relationship, a pick-up 1 headnormally' in registry with the supply magazine, means for imparting a uniform cycle of movement thereto for transporting the dielectric, one sheet at a time, from the supply magazine to the testing block, a selector head normally in registry with the testing block;and means for imparting'to said latter head a selective cycle of movement,said means including a normal transmission by which said selector head delivers to one of the collector magazines, and a selectortransmission for superimposing additional movement upon theflnormal movementof said head a testingcircuit, and a relay therein, responding to,

, the leakage of the dielectric sheet being tested to determine the-action of said: selective transmission. v 1

16.. A sheet dielectric classifying machine, comzines affixedlthereto, including a supply magazine and a collector magazine, an electrical test-- ing. block interposed between said magazines, a'

pick-up carriage and a selector carriage, a pickprising a bedhaving a plurality of sheet magaup head on the formercarriage normally registering with said supply magazine,- a selector head on the latter carriage'normally registering with said-testing block, means for moving said carriages in unison to shift the selector head from the testing block to the collector magazine, while concurrently moving the pick-up head from the supply magazine to the testing block, means for shifting the selector carriage relative to the pickup carriage; said means being responsive to a de-.

iparture from normal in an electrical characteristic of a sheet upon the testing block, to cause the selectorhead to transport an undesired sheet to.

be deposited outsideof the magazine and means to return the selector head to normal position after such operation.

7. A sheet dielectric classifying machine, comprising a bed having a plurality of sheet magazines affixed thereto, including a supply magazine and a collector magazine an electrical testing block interposed between said magazines,- a

pick-up head normally registering with said supply magazine, a selector head normally registering with said testing block, means 'for moving said heads upward for pick-upand downward for depositing acticn,-said means comprising a carrier responsiveto a departure from normal .in the electrical response of a sheet upon the testing block to cause the selector head to transport faisheet outside of predetermined specifications'kto' be deposited outside of the magazine, and means to return the selector headto n ormal:position after such'operation'.

d a. A sheetldiel ectric"classiiying machinecom prising a bedhavingfa plurality of sheet mag'a f zines afiixed thereto," including a" supply magazine and a 'collectormagazine, an electric'test} ing block interposed between said magazines, a,

pick-up carriage and a selector carriage,-a rai1 structure mounting said carriages, a pick-up head the selector headfrom the testing block to the collector magazine, while concurrently moving the pick-up head from the supply magazine tothe' testing-block an elevator track correlated'with both said" pick-up and said selector head to, change the elevation of said two heads concurrently,said carriage shifting means and said head elevating means being correlated for movement of the latter immediately before and immediately after the carriage sliding movement, meanseffectingrelease of the carried'sheet fromthe'respective. heads at the end of the delivery stroke of each of said heads,and means for shifting the selector carriage along therail relative to the supply carriage, saidfmeans being responsive to a departure from normal intheelectricalcharac- 'teristic of a sheet upon the testing blockj'to cause the selector head to transports; sheet outside of predetermined specifications to be deposited out side of the magazine; and means to return the 1 selector'head to normalposition after such operation. v

9. A sheet dielectric testingand classifying Ina- I chine comprising a bed, a supply magazine, a

collector magazine, an electrical testing blocl; in terposed-midway between said magazines "and a reject magazine beyond said collector magazine; a horizontal slide structure and a horizontal'elevator structure, a pick-up carriage affixed to said slide structure, a selector 'c'arriage'slidable with respect to said'slide'structures, a tractor frame affixed to said slide structure and connected to said selector carriage, each of said carriageshav 1 ing a tube vertically slida/ble therein, carrying respectively a pick-up head anda selector head at the lower end thereof normally registering respectively with the supply magazine and the test ing block, a horizontal elevator structure supporting-saidtubes, means for operating saidslide structure to advance the respective heads 'for registry of the pick-uphead with the test block and of the selector head with the collector mag for said heads vextendingtransversely thereof, and means for transporting said heads laterally to shift the selector head from registry with the testing block to registry with the collector magazine, and the pick-up head from registry with the I supply magazine to registry with the testing block, and means for shifting the selector head relative to the pick-up head,- said means being azine, meansfor. operating the elevator in timed relation therewith for: raising and lowering the tubesrespectivelyat the beginning and end of each stroke of the slide structure, and means controlled by the electricre'sponse in the testv operation toactuate the tractor frame for a defeci tive sheet, to slide the'selector carriage alongthe slide structure to cause registry of the selector head with the reject magazine.

10. In: a sheet dielectricclassifying machine," I the combination of a bed;a'supply'magazine and a collector magazine rising therefrom, an elec-- trical test block rising from said bed midway be- 17 tween said magazines, means for'applying testing current to a'sheet on said test block, and a reject magazine beside said collector magazine, a horizontal slide structure, meansslidably mounting the same, a pick-up carriage aflixed to said slide structure, a selector carriage slidable upon said slide structure, a tractor frame affixed to .said slide structure, a drag-linkconnecting] said tractor frame to said selector jcarriage, a pick-up tube vertically slidable in the pick-up carriage, a selector tube vertically slidable in the selector carriage, each of said tubes having a pick-up head at the lower end thereof, cross-bars affixed to the respective tubes, a horizontal elevator bar supporting said cross bars, and automatic means for sliding the slide structure to advance the carriages with the tubes thereon from the supply magazine to the testing block and from the testing block to the collector magazine respectively,

means in timed relation therewith for lifting and lowering the elevator bar to raise and" lower the respective tubes at the beginning'and end respectively of said slide movement, and means responsive to excessiveelectrical leakage in the testing operation to shift the drag link for moving the selector'carriage through an added displacement for delivery to the rejectmagazine,

11. In a sheet dielectric. classifying machine, the combination of a bed, a supply magazine, a collector magazine and a reject magazine rising 18 magazines and a reject magazine, a horizontal slide rail, bearings therefor, a pair of carriages upon said rail, one of saidicarriages being fixed upon said rail and having a pick-up tube 'vertic'allyslidable therein, the other carriage being slidable along said rail and having a'selector therefrom, a horizontal rail structure, means slidably mounting the same, a pick-up carriage and a tractor frame fixed upon'said rail structure, a selector carriage slidable upon said rail structure,

a drag-link connecting said tractor frame to said,

selector carriage, a suction pick-up'tubevertically slidable in the pick-up carriage, a suction selector tube vertically slidable in the selector carriage, a horizontal elevator, means on said tubesiresting upon said elevator, and automatic means for sliding the rail structure toadvance the suction tube verticallyslidable' therein, a tractor frame,

afilxed to said slide rail, a disk carrled by said frame, a drag-link pivoted tosaid disk at its advance end and to said sliding carriage at its trailing end, an elevator bar, means affixed to said tubes having bearing mount with respect to said'elevator bar to permit'sliding of said rail with'the carriages thereon and their tubes longitudinally of said elevator'bar, means for lifting and lowering said bar to raise and lower the pick-up and delivery tubes in their respective carriages, and with respect to the testingblock and magazines, a relay connected to operate under the excessive electrical leakage when a defective sheet is being tested and means controlled bysaid'relay to causefsaid disk to turn-for drawing the delivery carriage alo'ng the rail'by" traction transmittedthrough said drag-link, to bring the selector tube into magazinein such case. i i

14. An automatic classifying machine'for dielectric sheets comprising a supply magazine, a

collector magazine, an electrical "testing block midway between" said magazines and a reject magazine, "a horizontal slide rail, bearings therefor,.a pick-upand a selector carriage uponf'said rail, said pick-upcarriage being fixed uponsai'd rail and having a pick-up tube verticallyfslidabie therein, said selector carriage being slidable along said rail and having'a selector tube vertically slidable therein; suction heads upon the'lower endsof the respective'tub'es, a horizontal elevator bar supporting said tubes, a tractor frame affixed to said slide rail, having a rotatable disk thereon, a drag-link pivoted at one and near the periphery of said disk and at the otherend to saidselector carriage, said disk being normally freely mounted a range sufficient to cause its suction head and deliver to the reject magazine. 1

12. In an automatic sheet dielectricclassifying machine, asupply magazine, a collector magazine, a testing block midway between said magazines, a horizontal slide rail, bearings therefor, a pair of carriages upon said rail, 'one of said carriages being fixed upon said rail and having a pick-up tube vertically slidable therein, the

other carriage being slidable along said rail and I having a selector tube vertically slidable therein, tractor means fixed on said slide rail and connected to said slidable carriage, an elevator'bar, means aflixed to said tubes having bearing mount with respect to said elevator bar to permit sliding of said rail with the carriages thereon and with their tubes longitudinally of said elevator bar and means for lifting and lowering said elevator bar to raise andlower the pick-up and delivery tubes in their respective carriages and with respect to the testing block and magazines.

13 An automatic sheet dielectric testing machine comprising a supply magazine, a collector magazine, a testing block midway between said with said drag-link trailing,a relay under'control of the leakage current through the dielectric sheetbeing tested on the test block and means 'under control of said relay'whena defective sheet is being tested to causethe disk on the tractor frame to be driven for rotation thereof for a fraction of a revolution in the sliding movement of said slide rail thereby to advance the selector carriage alongthe rail'concurrently with thea'dvance of the rail itself to bring the selector tube into registry with the reject magazine, and means in timed'relation with-the movement of'the respectivecarria'ges to'raise and lower the elevator bar for lifting and lowering of the pick-up and selector tubes at the beginning and ends of the strokes of the rail for pick-up and r'elease'of the sheets "respectively carried by said tubes, and

automatic suction'and release control for said suction heads operating in timed relation with the machine.

' 15. An automatic classifying machine for di'-- electric sheets, comprising a supply magazine,

a collector magazine, an electrical testing block midway between saidm'agazi'nes and a reject magazine, a horizontal slide rail, bearings there-' for, a pick-up and a selector carriage upon said rail, said pick-up carriage being fixed upon said rail and having a pick-up tube vertically slidable therein, and said selector carriage being slidable along saidjrail and having a selector tube vertically slidable therein, a horizontal elevator bar supporting -;said tubes, means'responsive to the registry with the reject block to shift the selector carriage along the said means including a tractor frame aifixedto said rail, a diskrhaving an axle. through said tractor frame, a drag-link connecting said disk to said selector carriage a gear concentric with said v -e disk, a fixed rack meshing therewith, a pawl having a mount rigid with said disk, a ratchet wheel rigid with said gear and a solenoid actuated I a by the larger leakage'current through a;def-ec-;-

leakage through a defective sheet on rheaang move one of said headsaway 1 tance greater thanthat through which a satistivesheet to bring said pawl into coaction' with I,

near the periphery of said disk atone end to said the ratchet wheel for effectingpositiv'e drivev of the disk with-' the rotation or the gear asit moves along the rack, thereby to ,cai'ise the dr'ag link to be advanced with 'the rotatingdisk'gforjthe additional movement of theselector carriage re- I quired to effect delivery'therefrominto the rejectmagazine. 16. 'The combination recited in claim in "which the disk has a drum rigidJ therewith,,a

strap there'about, a tension reel mounting/the other end of said strap and stressed by the rotation of said disk resiliently totake up last motion. p 17.; In apparatus of the: character described, a mechanism for rejecting dielectricsheets foutnside of a given range of electricalcharacteristics, j said means comprising a tractor frame, means for laterallymoving' the same, said frameh'aving an .axle,,therethrough, a geaf'thereon, a fixed rack meshing therewith a dru'm'keyed to said axle, a .1 pawl pivoted upon. said drum, a ratchet wheel 1,afilxed with respect to said gear, means normally in retaining said pawl out or engagement'with said ratchet wheel and a relay responsive to the larger leakage current due to a defective sheet for permitting said pawl to engage said ratchet wheel,

thereby to cause said drum to be turned with said" a Y, gear in the movement of said tractor carriage, a {selector carriage for selectively transporting -tested sheets and a drag-link connecting saiddisk to said selector carriage to move the latter through the added stroke imparted by said drum whenever a defective sheet has been tested. 7 ,"IB EA ,dielectricsheet testing and classifying machine, comprising a pair of heads, means for raising and loweringthe' same, carriage means for the respective heads and serving to shift the 1 same horizontally, a supply magazine registers ing with one of said heads, a testing block regis- 'tering with the other of said heads, a cam shaft,

a cam thereon, linkage operated thereby forcontrolling the horizontal movement of said heads, a

secondcam on said shaft, linkage operated there-Q by for controllirigthe vertical movement of said: heads and means controlled by the excessive leakage current through a defectivesheet being tested to shift one of said heads away from the other for transporting the defective sheet to a point beyondth'at to which satisfactory sheets are delivered.

319,,A dieelectric sheet testing and classifying machine, comprising a pair' of suction heads, means for raising and lowering the same, carq riage means for shifting the same horizontally, a supply magazine registering with one of said heads, a testing block registering with the other r of said heads, a cam shaft, a cam thereon, linkagezoperated from said cam for controlling the horizontal movement of said heads, a second cam on said shaft, linkage operated thereby for controlling the vertical movement'of fsaid he'ads and means controlled by; the excessive leakage current through a defective sheetibeing tested to 1 20. In .a sheet dielectric classifyingma'chine,

a tractor frame, a selectorcar'riageiunder control;

the'reofisaid tractor frame having an axle therein, a disk keyed thereto, a dragelink pivoted'to i selector carriage at the othena gear'freelyrotat able upon said axle, a fixed rack meshing there.-

with', a pawl having a pivot rigid withsaid disk,

and means controlledby a characteristic of a 1 sheet departing from normalto bring said pawl into active operation for positive drive'of said disk from said-gearto advance theeselector carriagebythe'r'e'sultant advanceof the drag-link; I

21. "In an apparatus or the characterdescribed,

a tractor device comprising a frame, an axle therein, a drum keyed to said axle, a disk keyed I to said axle, a gear freely rotatable upon's'aidz axle, a" fixed rack meshing with. said gear, a ratchet wheel rigid with said gear, a pawl pivoted to ,said drum, atension reel carried byfsaid a v frame, a strap connecting said reel to 'said:dr.um,j a testing circuit and means under control of test leakage current through asheet' that is below specifications, to cause the pawl to engage the ratchet andth'ereby todrive the disk 'ahdthe drum, underthe impulse of the gear rollingon the rack in the advance movement of the tractor frame, v r I v r 22. .In a machine for automatically segregating dielectric sheets below specifications, the cornbination of a source of sheets to be tested, a col v lector magazine for those that meet specifications, .a testing block, means for delivering sheets in succession to the testing blockJaselector car-f riage for transporting the tested sheets,and an 7 auxiliary transmissionfor imparting an added 1 motion :to the selector carriage where the sheet transported thereby is below speciflcationssaid transmission being responsive to excess leakage current through a sheet on the testing blocks 23.- The combination recited in claim-22 in, which arelay is provided responding to such excess leakage current, said auxiliary transmission is under control of said relay, and means effec tive to return the selector carriage to initial posithereof. e

24. 'In an automatic machine for selecting dition, after the completion of said added motion electric sheets that are'up to specification and discarding those below specification, the combination of a source of supply for the sheets,-a testing block means for electrically testing sheets in sequence upon said block, and a collector magazine for thesheets that are up to specification, meansv including a selector head 'coacting with said testing blockand adapted to transport the successively tested sheets selectively to the collector magazine as to those that are up to specie iications'and beyond the collector magazine as to Y those that are below specifications, the combination of a slide-rail structure, means'for imparting a uniform rebiprocatory stroke thereto, atractor frame aflixed to-saidslide rail structure, a'selec- '1,

tor frame-carrying said selector'head'and slidable upon said slide rail structure, aerelay responding on' test to the high leakage current through a'defrom the other V for advancing thedefective sheet througha dis-r 21 fective sheet, a normally inoperative transmission in said tractor frame, means under control of said relay to render said transmission operative for imparting a tractive impulse to the tractor frame, for corresponding sliding advance of said selector frame along the slide rail for the reject action, as the slide rail is shifted with as tractor frame, means under control of said slide rail at the conclusion of its movement for interrupting said relay circuit, and means resiliently to take up lost motion during the operation of said tractor transmission.

25. In an automatic sheet dielectric classifying machine, the combination of alternating current power mains, a testing block, means for feeding sheets successively to said block, means for closing the circuitthrough a sheet on said block, including a timer, a relay in said circuit ineffective under the'small leakage through a sheet up to specification but operative under the higher leakage through a defective sheet, .a primary transmission to transport to a collector a sheet up to specifications, an auxiliary transmission under control of said relay to transport through an additional path and beyond said collector a sheet below specification, said means including an operating relay closed by said test relay, means connecting said operating relay directly to the power mains independently of the reopening of said test relay, and a switch under the operation of one of said transmissions to interrupt said operating relay circuit at the conclusion of the auxiliary transmitting operation, thereby to permit return of the parts to normal position.

26. In an automatic sheet dielectric classifying machine, the combination of alternating current mains, a high voltage transformer operated from said mains, a high voltage sheet testing circuit across the secondary of said transformer, means including a timer for momentarily applying the testing impulse in said sheet testing circuit, a test relay in said high voltage circuit responsive to the greater leakage current through a defective sheet, an operating relay in circuit with said test relay, a holding relay in parallel therewith, said operating and said holding relays being connected directly across said power mains to maintain'their circuit regardless of the reopening of said test relay, a primary transmission for transporting a tested sheet to selected position, an auxiliary transmission under control of said operating relay for imparting an additional displacement to the sheet carried by said primary transmission when the test shows a defect therein, and a switch in the circuit of said operating and holding relays under control of one of said transmissions to open circuit at the conclusion of the auxiliary transmission action.

27. In an automatic sheet classifying machine, the combination of power mains, a driving motor for the machine operated therefrom, supply and collector magazines for the sheets being classified, each having a follower therein, and a primary transmission for delivering tested sheets to the collector magazine, a high voltage testing circuit operated from said mains, including timer means for momentarily closing circuit to a sheet being tested, said circuit also including a test relay responsive to the high leakage through a defective sheet, an operating relay actuated by the operation of said test relay, means for actuating said operating relay from the mains after opening of the test relay circuit, auxiliary transmission means. under control of said operating relay for moving such defective sheet through an additional displacement todiscard position, a switch in said operating relay circuit, means under concuit, said relay being of the type requiring manual actuation for restarting the machine.

28. In an automatic sheet dielectric classifying machine, the combination of a bed, a supply magazine having a follower thereon, a testing block and a collector magazine rising therefrom, a horizontal slide rail, a pick-up'carriage afiixed thereon and havin a vertically slidable pick-up head mounted therein, normally in registry with the supply magazine, a selector carriage slidable on said rail and having a vertically slidable selector head mounted therein normally in registry with said testing block, means for effecting a vertical movement of said heads, means for effecting a fixed horizontal movement of said slide rail, means for applying suction to said heads in their pick-up action and releasing the suction in the deposit action, means for, applying a testing impulse to a sheet on the testing block, spring means for urging the follower stack in the supply magazine upward during the pick-up action and means for normally braking the spring impelled movement of said follower, a single cam shaft for controlling all of said operations, said cam shaft having an elevator cam thereon for controlling the up and down movement of the heads, a transfer cam for controlling the back and forward movement of the slide rail, a pneumatic control cam for applying and releasing the suction for the pick-up and deposit actions respectively, and means under control of one of said cams for momentarily releasing the brake in correctly timed relationship to permit spring-lifting of the follower in the supply magazine, said means comprising an enlargement on one of said cams and a brake release lever under control of said enlargement.

29. The combination recited in claim 28 in which an electric timer is mounted on said cam shaft for applying the testing impulse by closing the testing circuit in correct phase relation with the operation set forth.

30. An automatic machine for selecting dielectric sheets, includin means for subjecting such sheets successively to electrical test, means for transferring 'the sheets that test normal, through a uniform distance, and means responsive to a deficiency in the test of a sheet to increase the speed and thereby lengthen the distance of said transfer.

31. In a machine for classifying dielectric sheets and of the type that comprises an electrical testing block, a supplymagazine, means for .picking up sheets successively from the top of said magazine and transferring them succes-' sively to the testing block, means for applying electrical testing impulse to the-sheet on the testing block, a plurality of collector magazines, and selective means responsive to the current leakage through the tested sheet, selectively to transfer the sheets in accordance With their grading to the corresponding collector magazine; the combination in which the testing =block comprises an insulating hollow standard, a conductling rod, therein, a. platform in the upper end bf said standard for supporting the Heet t6 be f tested and a spring interposed betwensaid fed 7 and said platform to peimi t the Iagtfier resiliently 1 Co take the thrust of a. circuit "closing head when 3 pressedagainst sfii'd platfei'm.

32, The combifltion recitefi m elem 31 m which an a1; blower nozzle fee'ds int b sag-d standard immediately below said perforated pltfgrm. v

R. rsprrm'r'r. REFERENCES-CITED. I I The following fefei'enees are bf r'ee'b1fd in the file of this patent:

' Number 

